Chapter 7, Problem 7.45P

. A 2 m tall barrel is closed on top except for a thin pipe extending 8 m up from the top. When the barrel is filled with water up to the base of the pipe (2 m deep), the water pressure on the bottom of the barrel is 20 KPa. What is the pressure on the bottom when water is added to fill the pipe to its top?

For a pumper truck pumping water to a fire, the back pressure is the additional pressure on the pump caused by the height of the nozzle. (Another way of thinking of back pressure is as the minimum pressure the pumper must produce in order to make water flow out the end of the nozzle.) Consider a pumper at street level pumping water through a hose to firefighters on the top of the ninth floor of a building. If each floor is 16 feet high, what is the head of water at the mouth of the nozzle?

A leaky bucket of fluid is lifted 10 feet. It is lifted at a constant rate and leaks at a constant rate. It is 50 lb at the start and 30 lb at the end.  How much work was done on the fluid; assume a density of ρ lb per cubic feet?